1. Field of the Invention
The present invention relates to a pattern-forming method capable of forming a further miniaturized pattern by reducing a separation size between resist patterns or a pattern opening size already formed in forming the resist patterns in a semiconductor process, as well as using a super fine pattern-forming material capable of forming a super fine pattern restricting a film thickness of a crosslinked film while preventing a developing defect, which are difficult to achieve at the same time, by using an amine compound-containing developing solution.
2. Background Art
In an extensive field including manufacture of a semiconductor element such as LSI, production of a liquid crystal display surface of an LCD panel, and manufacture of a circuit substrate of a thermal head or the like, a resist pattern is formed on the substrate for formation of a micro element or micro fabrication. In formation of the resist pattern, there is used a so-called photo lithography method of performing developing treatment after a photosensitivity resin composition is exposed by selective illumination of active rays such as ultraviolet rays, far ultraviolet rays, excimer lasers, X-rays, and electron rays. In this photo lithography method, a positive type or negative type photosensitivity resin composition is used for forming the resist pattern.
Recently wiring and a separation width required in the manufacturing process have been increasingly miniaturized caused by high-integration of semiconductor devices or the like, and an exposure apparatus using a short-wavelength light source such as g-lines, i-lines, and excimer lasers corresponding to this trend is used, and a phase shift mask or the like is used at the time of the exposure in some exposure apparatuses. It is, however, difficult to form a miniaturization resist pattern exceeding the wavelength limit in the photo lithography by the conventional exposure, and also an exposure apparatus for the short-wavelength or an apparatus using the phase shift mask or the like is expensive. Therefore, there has been studied a method of effectively miniaturizing a resist pattern, which is formed using the conventional, known pattern-forming apparatus and the conventional, known positive type or negative type photosensitivity resin composition without use of such expensive apparatus.
One method of effectively miniaturizing a resist pattern is proposed. In the method, after a pattern formation is made by the conventional method in use of a known photosensitivity resin composition, for example, a chemical amplifying type photo resist, a coated layer made of a super fine pattern-forming material containing a water-soluble resin is formed on the formed resist pattern, and the resist is heated or exposed, thereby acid generated in the resist or acid contained in the resist is dispersed into the coated layer, the coated layer in the vicinity of the resist is crosslinked and cured by the dispersed acid, thereafter the first formed resist pattern is covered with the crosslinked film by removing the non-crosslinked coated layer to thicken the resist pattern, resultantly the width between the resist patterns, a separation size or a hole opening size of the resist is reduced to miniaturize the resist pattern, and the super fine resist pattern equal to or less than the resolution limit is effectively formed (refer to Japanese Unexamined Patent Publication No. 5-241348, No. 6-250379, No. 10-73927 and No. 11-204399).
Presently, in a case where after a super fine pattern-forming material is coated on the resist pattern to form a coated layer, which is heated and/or exposed, the resist pattern is developed to effectively form a super fine resist pattern equal to or less than the resolution limit, a developing solution composed of an exclusive developing solution (for example, refer to Japanese Unexamined Patent Publication No. 2002-49161) or a mixing solution of water and a water-soluble organic solvent is used for removing the non-crosslinked coated layer. Since the resist pattern is smaller in size than the conventional one caused by the progress of the lithography technology, in a case where the pattern size is further miniaturized by using the super fine pattern-forming material, there is an increasing demand for restricting the film thickness of the crosslinked film. In order to meet such demand, in an exclusive developing solution composed of water and water-soluble organic solvent and in purified water developing, an amount of a water-soluble crosslinking agent in the super fine pattern-forming material is reduced, or a temperature in performing a crosslinking reaction is lowered for restricting the film thickness of the crosslinked film. However, when the film thickness of the crosslinked film is adapted to be restricted in such a method, the crosslinking density of the crosslinked film is reduced to possibly generate developing defects frequently. That is, according to the conventional method, it is difficult to prevent occurrence of the developing defects, as well as at the same time, restricting the film thickness of the crosslinked coated film.